Structural element



Jan. 27, 1942. KlESER 2,271,079

STRUCTURAL ELEMENT Filed June 14, 1959 v By atla weya" Patented Jan. 27,1942 UNITED STATES PATENT OFFICE Application June 14, 1939, Serial No.279,221 In Germany June 16,1937

8 Claims.

This invention relates to structural elements of colfered, box-like, orcellular construction, that is, formed with open-mouthed box likerecesses or spaces which are closed by assembling a plurality of theelements in contact with each other and with opposing coffers or cellsin register, the closed spaces thus formed being filled with concrete orcement to unite the elements.

An object of the invention is to provide coffered structural elementsapplicable to a wide range of constructions.

Another object of the invention is to provide such elements with coffersof standardised form enabling the elements to be assembled in transverseas well as in parallel relation.

The structural elements according to the invention are of substantiallyrectangular cross section, of width exceeding th depth, and coffers orcells may be provided in both of the narrow sides of the elementcorresponding to the depth dimension. One of the wider sides of theelement may be continuous and fiat whil the other side presents theopenings of the middle or main coffers of the element.

The coffers are separated by ribs which may have thin portions formed inthem to facilitate the breaking through of openings for the passage ofreinforcing members and pouring of cement.

The drawing shows a perspective View of a structural element.

The structural element is a box girder with middle and side cofiers orcellular spaces.

The fiat thin web which forms the base of the middle box likecompartments or coffers I and the level under surface of th structuralelement is marked l9. Each of the sides 5 of the structural element hasupper and lower flanges 2 and 3 in which are embedded longitudinalreinforcing irons 20, said flanges equally being connected by a webportion I l. The inner surfaces of the sides 5 of the middle coffers areinclined inwardly and downwardly.

The web portions H separate the middle coffers and the side coffers,ribs l2 are provided between the middle coffers and ribs l3 between theside coffers. Ridges l4 extend outwardly from the longitudinal flanges 2and 3 to form the upper and lower boundaries of the side coffers, andthe spacing ribs l3 extend across from the upper to the lower ridges.The outer surfaces of the ribs l3 and ridges l4 lie in one and the sameplane.

Rectangular recesses l2 are provided in the ribs l2 between the middlecoffers indicated by 9, and recesses l between the middle and sidecoffers. The walls 1 of the ribs [2 are arranged girder of substantiallyrectangular form in cross section the width being greater than thedepth, said element comprising side portions, a bottom portionconnecting said side walls, a plurality of uniformly spaced websextending transversely from one side portion of the element to the otherside portion to form a series of middle coffers,

in said element, external ridge extending longitudinally along at leastone of said side portions at the top and bottom thereof and forming alongitudinal channel in said side portion and a plurality of uniformlyspaced ribs extending across said side portion fromridge to ridge anddividing said channel into side colfers.

2. A structural element according to claim 1, in which the base surfaceof the bottom portion is planar.

3. Structural element consisting of a boxgirder like structure ofgreater width than depth with middle coffers in one broad side, and sidecoffers in both narrow sides of the element, said side coffers andmiddle coffers being of equal dimensions measured longitudinally of theelement.

4. Structural element according to claim 3 in which each middle cofferhas two opposite inner walls substantially planar and with an equal andopposite inclination to one another.

5. A structural element according to claim 1 in which the base surfaceof the bottom portion is planar and the edge of the ridges and ribsdefining the coffers in a side portion lie in one sides of thestructure.

KARL KIESER.

